The first, the Avro 707, VX784 first flew from Boscombe Down on 4 September 1949 with S.E. "Red" Esler, at the controls. The prototype crashed less than a month later, on 30 September, near Blackbushe. The next prototype, VX790, renamed the 707B, had a longer nose, different cockpit canopy, a wing of different (51°) sweep and a longer nose wheel leg to provide the high angle of incidence required by deltas for landing and take off. The 707B was given the same dorsal engine intake as the 707, although this was later modified to a NACA design. It first flew on 6 September 1950. Both these aircraft were built to test low speed characteristics.

A second 707A WZ736 was built to speed the development programme, making its maiden fight on 20 February 1953.
WZ736 is preserved at the Museum of Science and Industry in Manchester.
You are looking for a small tupperware container.
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